Final Exam Heater Review

Question 1

What is the purpose of AD CF 90 03R2?

Answer 1

To avoid Carbon Monoxide poisoning in the cabin

Question 2

What happens when you turn the Combustion Heater “ON”?

Answer 2

Combustion blower starts,

makes pressure switch, turns

on ignition, then fuel supply.

Ventilating fan also comes on

when on ground.

Adjust cabin thermostat

above actually temp, fuel

solenoid actuated at heater.

Combustion occurs and heat

is generated to inner sleeve

where air passes over top

being warmed

Question 3

What does the “Duct Limit Switch” do?

Answer 3

Shuts off fuel if not enough airflow to carry heat out

Or if duct temp reaches its maximum

Automatically resets when duct temp comes down to

acceptable level

Question 4

What does the “Overheat Switch” do?

Answer 4

much higher than Duct switch but below fire

hazard

Shuts off combustion airflow, fuel supply, & ignition.

Warning light illuminates

Cannot be reset, until on the ground

Question 5

What are the effects of carbon formation on the fuel nozzle after heater shut down?

Answer 5

Weak heat